This relates generally to electronic devices, and more particularly, to joining electronic device structures using adhesive.
Adhesives are widely used to assemble components for electronic devices such as computers, cellular telephones, media players, and other electronic equipment. For example, sheets of pressure sensitive adhesive are often used to join planar structures. Planar structures may, for example, be laminated together with pressure sensitive adhesive using lamination equipment. Pressure sensitive adhesive layers are, however, only able to accommodate a limited amount of surface topology. When pressure sensitive adhesive layers are used to join structures with substantial step heights or other abrupt features, there is a risk that bubbles or voids may develop. The risk of bubble formation may be reduced by using softer pressure sensitive adhesive materials, but this tends to weaken bond strength and other desirable properties.
Liquid adhesives can be used to overcome step height discontinuities, because liquid adhesives can flow over abrupt features. However, the process of joining electronic device structures using liquid adhesives is often disfavored because of the challenges associated with using liquid adhesives in a production environment.
It would therefore be desirable to be able to provide improved ways to join structures such as electronic device structures using adhesive.